<?php
/**
 * OpenID protocol key-value/comma-newline format parsing and
 * serialization
 *
 * PHP versions 4 and 5
 *
 * LICENSE: See the COPYING file included in this distribution.
 *
 * @access private
 * @package OpenID
 * @author JanRain, Inc. <openid@janrain.com>
 * @copyright 2005-2008 Janrain, Inc.
 * @license http://www.apache.org/licenses/LICENSE-2.0 Apache
 */

/**
 * Container for key-value/comma-newline OpenID format and parsing
 */
class Auth_OpenID_KVForm {

  /**
   * Convert an OpenID colon/newline separated string into an
   * associative array
   *
   * @static
   * @access private
   */
  function toArray($kvs, $strict = false) {
    $lines = explode("\n", $kvs);
    
    $last = array_pop($lines);
    if ($last !== '') {
      array_push($lines, $last);
      if ($strict) {
        return false;
      }
    }
    
    $values = array();
    
    for ($lineno = 0; $lineno < count($lines); $lineno ++) {
      $line = $lines[$lineno];
      $kv = explode(':', $line, 2);
      if (count($kv) != 2) {
        if ($strict) {
          return false;
        }
        continue;
      }
      
      $key = $kv[0];
      $tkey = trim($key);
      if ($tkey != $key) {
        if ($strict) {
          return false;
        }
      }
      
      $value = $kv[1];
      $tval = trim($value);
      if ($tval != $value) {
        if ($strict) {
          return false;
        }
      }
      
      $values[$tkey] = $tval;
    }
    
    return $values;
  }

  /**
   * Convert an array into an OpenID colon/newline separated string
   *
   * @static
   * @access private
   */
  function fromArray($values) {
    if ($values === null) {
      return null;
    }
    
    ksort($values);
    
    $serialized = '';
    foreach ($values as $key => $value) {
      if (is_array($value)) {
        list($key, $value) = array($value[0], $value[1]);
      }
      
      if (strpos($key, ':') !== false) {
        return null;
      }
      
      if (strpos($key, "\n") !== false) {
        return null;
      }
      
      if (strpos($value, "\n") !== false) {
        return null;
      }
      $serialized .= "$key:$value\n";
    }
    return $serialized;
  }
}
